Twitter @Anywhere in Ext.Panel

I'm trying to get my app able to share a URL using Twitter.
As my Sencha Touch app is essentially HTML I assume I can use Twitter's @Anywhere Tweetbox (https://dev.twitter.com/docs/anywhere/welcome#tweetbox) within a Ext.Panel. However it does not work in my Sencha app.

This is my web inspector, not there is no <head> or <body> tags even though I had typed them into the panel html parameter.

If I am correct in my assumption the panel is trying to load this all into the <body>, then is there a way around this so I can use the full HTML file and thus, enable the Twitter tweet box in my application?